Note 176 — ON THE WILL IN NATURE. [190]

In the Scholium to the eighth of the definitions he has placed at the top of his "Principia," Newton quite rightly distinguishes absolute, that is, empty, from relative, or filled Time, and likewise absolute from relative Space. He says, p. 11: Tempus, spatium, locum, motum, ut omnibus notissima, non definio. Notandum tamen quod VULGUS (that is, professors like those I have been mentioning) quantitates hasce non aliter quam ex relatione ad sensibilia concipiat. Et inde oriuntur præjudicia quædam, quibus tollendis convenit easdem in absolutas et relativas, veras et apparentes, mathematicas et vulgares distingui. And again (p. 12):

I. Tempus absolutum, verum et mathematicum, in se et natura sua sine relatione ad externum quodvis, æquabiliter fluit, alioque nomine dicitur Duratio: relativum, apparens et vulgare est sensibilis et externa quævis Durationis per motum mensura (seu accurata seu inæquabilis) quâ vulgus vice veri temporis utitur; ut Hora, Dies, Mensis, Annus.

II. Spatiam absolutum, natura sua sine relatione ad externum quodvis, semper manet similare et immobile: relativum est spatii hujus mensura seu dimensio quælibet mobilis, quæ a sensibus nostris per situm suum ad corpora definitur, et a vulgo pro spatio immobili usurpatur: uti dimensio spatii subterranei, ærei vel coelestis definita per situm suum ad terram.

But even Newton never dreamt of asking how we know these two infinite entities, Space and Time; since, as he here impresses on us, they do not fall within the range of the senses; and how we know them moreover so intimately, that we are able to indicate their whole nature and rule down to the minutest detail. [Add. to 3rd ed.]